A study in the Royal Society journal Biology Letters this week shows that people with wide faces might be more prone to aggression than those with long faces.

Observers readily attribute behaviours and personalities on the basis of facial appearance. In particular the ratio of the width of a person’s face to the height of their face has sometimes been suggested as a cue to aggression but there is little scientific research proving a link. The scientists behind the study published today set about figuring out if there really is a correlation.

Analysing the faces of 103 students from the University of Bristol the team found that students with wider faces self-reported themselves to be more aggressive. The researchers measured how wide the students’ faces were and divided the measurement by the height of their faces. They compared the resulting score with how aggressive the students reported themselves to be. The team found that as facial width to height increased so did verbal aggression, physical aggression and anger.

Comparing the results between the female and male students in the study, the team found that while for female volunteers high facial width to height ratios correlated with verbal aggression, the scores for male students showed that a higher facial width to height ratio was linked to dominance as well as aggression and anger.

The team also looked at whether facial masculinity was a good indicator of how aggressive their volunteers reported themselves to be but found that there was no correlation.

The team found a significant correlation between faces with high width to height ratios and aggression but say the reason for the link is unclear. ‘One explanation might be that larger, stronger cheek bones are better able to withstand fracture from blows to the head, which may in turn be more likely to occur in more aggressive individuals,’ say the team. ‘Cheek bone fractures are the second most common facial fracture, they are predominantly observed in young men and are almost always caused by assault,’ they add.